Pump



R. KALETSCH June 5, 1962 PUMP Filed Sept. 24, 1958 5 Sheets-Sheet 1 fm efian' RE/NHOLD KALETSCH Af/omeys June 5, 1962 R. KALETSCH 3,037,686

PUMP

Filed Sept. 24, 1958 3 Sheets-Sheet 2 RE/NHOLD KALETSCH ,a mm am Inventor:

Alia/ways June 5, 1962 1 R. KALETSCH 3,037,686

PUMP

Filed Sept; 2 1958 s Sheets-Sheet 3 4 42 Fig-3 INVENTOR RE/NHOLD KALEHSGH ATTORNEYS Claims priority, application Germany Oct. 1, 1957 3 Claims. (Cl. 230-162) The present invention relates to pumps. More in particular the present invention relates to pumps for conveying and compressing gaseous pressure mediums and more particularly still to a pump for inflating camping and the like equipment.

Camping and the like equipment consisting of rubber or the like material suitable for inflation were blown up heretofore by air pumps operated by hand or foot. The inflating operation was consequently very time-consuming and costly. If the inflating is done with the aid of the human lungs this procedure is even more tiresome and harmful to the rubber material since the human breath has a certain humidity entering into the interior of the inflated equipment. In addition, this method is harmful to the person using ones lungs and may cause sensation of dizziness; cramps and prolonged headaches.

It is an object of the present invention to provide a pump for inflating camping and the like equipment, which operates in a simple and eflicient manner, and finishes the inflation in a very short period without requiring any considerable human effort.

It is another object of the present invention to provide a pump for inflating camping and the like equipment, with which comparatively high pressures can be obtained in a very short time.

The present invention will be better understood upon the following description of the accompanying drawings, wherein:

FIGURE 1 is a somewhat schematic longitudinal sectional view of the pump of the present invention;

FIGURE 2 is a somewhat schematic longitudinal sectional view of another embodiment of the pump of the present invention adapted for obtaining higher pressures;

FIGURE 3 is a somewhat schematic longitudinal sectional view of another embodiment of the pump of the present invention adapted for obtaining still higher pressures.

Referring to the drawings more in detail and turning first to FIGURE 1, the conical mouthpiece of hose 2 is shown slipped upon the exhaust pipe 1 of a motor as, for example, an automobile motor.

The conical mouthpiece 2 of the hose adjoins a cylindrical part 3 having an opening 4a and bearing above the opening a rectangular flange 3a. A pressure spring 5 is fastened with one end against the portion of the flange extending parallel to the cylindrical hose by means of a screw 5a. At its other end the pressure spring 5 is attached to a safety valve 4 tending to press the same against the cylindrical portion 3, so as to close the opening 4a thereby maintaining the required pressure difference between the interior of the cylindrical part 3 and the outside.

The pressure spring is so adjusted that the desired pressure diflierence is maintained.

Into the interior of the cylindrical part 3 there projects a cylinder 6.

The cylinder 6 has a smaller diameter than cylinder 3 and it is hermetically connected with the latter by means of an interposed fitting ring 7. At the end facing the exhaust pipe the cylinder 6 is closed by a front wall portion 9. In its cylindrical portion above the ring 7 the cylinder has one or several openings 8 and below the ring it has one or several openings 10 which are preferably somewhat greater than openings 8. A sleeve 11 is disnited States posed inside the cylinder 6 comparatively tightly fitting to the interior walls of the latter but still being axially displaceable therein. This sleeve has openings 12 provided at the side adjacent to the portion of cylinder 6 having the openings 8 and 10. The lower portion of cylinder 6 leads to the pump casing 13. This casing 13 is divided by a membrane 14 disposed therein into two compartments, an upper compartment 23 and a lower compartment 16. In the portion of the compartment 16 there is provided an inlet check valve 15. Another check valve 17, which is preferably somewhat smaller than the check valve 15, is disposed at the lowermost end of the compartment 16. At the same location there is mounted to the casing 13 an outlet pipe 18 communicating with the compartment 16 via the check valve 17 and conducting the compressed pressure medium to the device 19 which is to be inflated.

A coil spring 20 is fixed with one end to the bottom portion of compartment 16 and with the other end to a screw connection 21 in the central portion of membrane 14 and exercises a slight, predetermined pressure against the membrane 14, thereby tending to press the same in upward direction against the influence of the pressure medium in the compartment 23.

The screw connection 21 is also connected to the one end of the intermediate member 22. The other end of the intermediate member 22 is connected to a bolt 25 mounted against the inner wall of sleeve 11. One end of the bolt 25 projects through the sleeve 11 and the cylinder 6 thereby securing the sleeve 11 against rotary displacement and, as it projects through a longitudinal slot in the sleeve 11 it also prevents the sleeve 11 from being moved upwardly and downwardly beyond a limit determined by the length of the longitudinal slot 25a. The length of this slot is so chosen that the openings 12 in the sleeve 11 are always situated concentrically with the openings 8 and 10 in the cylinder 6.

Preferably a resilient intermediate member 22 is used, such as a tension or pressure spring and resting means 24 are provided hingedly joined to the end of bolt 25 projecting through cylinder 6. By means of hinge 24a these arresting means 24 will keep the sleeve 11 in its respective positions, i.e. either in the position in which the openings 12 are above the openings 8 or in the position in which the openings 12 are above the openings 10.

Instead of the mouthpiece of a hose 2, a conical, perforated plug of resilient material can be used, which is inserted into the end of the exhaust pipe of a motor.

The check valves may consist, for example, of small plates composed of rigid or elastic material, slightly pressed against corresponding inlet or outlet openings in the casing 13.

Operation In the position shown in FIGURE 1 the openings 12 are above the openings 8 and consequently exhaust gases pass through exhaust pipe 1. The conical pipe 2 and cylinder 3, are allowed to enter into the sleeve 11 and from there to pass into the compartment 23 of casing 13. The exhaust gases then press the membrane 14 downwardly. The membranepulls along the sleeve 11 via the member 22 and bar 25 until the openings 12 are located concentrically above the openings 10 of the cylinder 6 thereby venting the compartment 23.

Under the influence of spring 20 the membrane 14 is then pushed back in upward direction; shortly before reaching its highest portion the membrane 14 pushes the sleeve 11 upwardly via the member 22 and the bar 25 until the openings 12 are concentrically situated above the openings 8 in the cylinder 6, While the lower openings 10 are closed by the integral lower portion of sleeve 11. Thus, communication between sleeve 11 and compartment 23 on the one hand and cylinder 6, conical 3 portion 2 and the exhaust pipe 1 on the other hand is reestablished and the exhaust gases may enter into the compartment 23 and can push down the membrane 14.

Due to this reciprocating movement of membrane 14 actuated by the gases leaving the exhaust pipe 1 and controlled by the sliding sleeve 11, a pumping action is produced and air sucked into the compartment 16 through the inlet check valve 15 during the upward movement of membrane 14 is pushed out of the compartment 16 through the outlet check valve 17 into the outlet pipe 18 and from there into the device to be inflated during the downward movement of membrane 14.

The use of a resilient intermediate member 22 e.g. a tension and pressure spring as shown in FIGURE 1 of the drawings results in a certain phase displacement between the respective movements of membrane 14 and the sleeve 11. If the pressure in the device 19 increases in the course of inflation the counter pressure of the resilient intermediate member 22 slows down the downward movement of the membrane 14. This displacement of phase becomes continuously smaller until the pump comes to a standstill during the period in which the sleeve 11 passes the dead center, i.e. that range of its position relative to the cylinder 6 in which the openings 12 are located between the openings 8 and 10 and possibly establish a communication with the cylinder 3 via a portion of the openings 8 and the outside via a portion of the openings 10. The stream of the exhaust gases is thereby checked to a certain extent but still they are allowed to evade through the openings 10. It is therefore unnecessary to provide a special safety valve.

As soon as the pressure in the inflated device 19 decreases this balance is disturbed and the reciprocating movement of the membrane 14 and the sleeve 11 is restarted under the influence of the exhaust gases.

The ultimate pressure in the device inflated by the pump of the present invention is thus determined by the weight of the sleeve 11, the force of springs 20 and 22 and the extension, the arrangement and the relative distance of the openings 8, 10 and 12. Consequently the ultimate pressure can be determined by dimensioning these factors accordingly. In addition, the ultimate pressure is further increased by supplying additional exhaust gas to the pump thereby delaying the movement in which the downward movement of the membrane 14 is slowed down which would bring the pump to a standstill. This can be easily done by pressing the gas pedal of the automobile so that it is very easy and simple to bring the device to be inflated to the desired pressure level. If the device is equipped with the arresting means 24 mentioned further above and with the resilient member 22 in the form of a tension and pressure spring, the sleeve 11 is caused to perform interrupted jerking movements rather than sliding motions as the sleeve is maintained in its respective end positions by the arresting means. The sleeve 11 is thus caused to move only whenever the membrane 14 has reached its uppermost and lowermost end-positions, respectively and the sleeve 11 is thus snapped from the inlet position to the outlet position and vice versa.

According to another preferred embodiment of the pump of the present invention, provision is made for several pressure stages which enable the establishment of higher pressures and make it possible to use the pump for high pressure objects such as e.g. automobile tyres.

Such a pump may either be equipped with a membrane just like the single-stage pump shown in FIGURE 1 and described here before or with pistons or with both. In the embodiment shown in FIGURE 2 the second stage consists of a piston pump unit 26. The unit comprises a cylinder 28 housing a piston 27 adapted for reciprocating movement therein mounted at the lower end of a connecting rod 33. An outlet check valve 29 is provided at the lowermost end or the base plate 28a of the cylinder 28 and an inlet check valve 30 is provided in the piston 27. At the base plate 28a of the cylinder 28 there is also mounted a pipe connecting the cylinder 28 with the device to be inflated and with another pipe conduit 34 having in its lower portion a check valve 36 adapted to make the latter communicate with the pipe 35, having a three-way-cock 37 in its middle portion and connected at its upper end with the casing 13 of the first stage. The first stage is substantially composed just l ke the pump shown in FIGURE 1 with the casing 13 hav ng a membrane 31 instead of the membrane 14 and similar to bellows and having at its lower end a base plate 32. The connecting rod 33 of the second unit is mounted with its upper end against the base plate 32 of the unit for the first stage. The base plate 32 tightly seals the membrane 31 against the compartment in the casing 13 thereby separating the interior of the bellows 23 from the space 16 defined by its outside and the casing 13. The exhaust gases passing to the interior of the bellows filling the space 23, whenever the sleeve 11 is so positioned that its openings 12 are above the openings 8 in the cylinder 6, push the base plate 32 in downward direction precompressing the air within the space 16 and forcing the same into the conduit 34 and through the valve 36 into the conduit 35 as long as the device 19 to be inflated has a comparatively low pressure inside so that comparatively little pressure is required to continue the inflation. The only slightly compressed air of the chamber 16 of the unit of the first stage is used for the inflation; this air is conveyed to the device 19 directly via the conduit 34, the check valve 36 and the conduit 35. As the pressure in the device 19 increases and as soon as the pressure produced by the first stage is suflicient to overcome the tendency of the check valve 36 to close the conduit 34 against the conduit 35, the movement of the base plate 32 is arrested and the supply of air from the first stage is halted. The three-way-cock 37 is then turned from its position shown in FIGURE 2 counterclockwise by an angle of thereby establishing communication between the upper portion of conduit 35 and hence the compartment 16 and the outside via the opening 34a and the pipe conduit 34. As a consequence the pressure balance between the outside and compartment 16 enables the base plate 32 to restart moving under the influence of the excess pressure in the space 23. Simultaneously with the base plate 32 the piston 37 is moved downwardly in the cylinder 26 and the air in the cylinder is compressed and pushed via the check valve 29 into the conduit 35 and from there into the device to be further inflated. Due to the small cross section of the piston compared with that of the base plate 32 the pressure in the space 23 is multiplied and the pressure in the inflated device can be further increased.

The provision of this second stage makes it possible to reach much higher pressure in the inflated device. At the same time the performance of the first stage during the initial inflating operation greatly speeds up the entire process, and this multistage pump operates much faster than a pump using only the unit of the second stage. It is, of course, absolutely possible to use only the second stage. In that case the second check valves 15 and 36 can be dispensed with and a simple air passage at the respective locations where these valves are located is suflicient.

For very high pressures multistage pumps can be used shown, for example, in FIGURE 3 in which there are provided two cylinders 38 and 39. The one end of the piston rod 33 is attached in the center of the lower surface of base plate 32. At the other end of connecting rod 33 there is provided a first piston 41 shuttling back and forth in the cylinder 38. At the end of the piston rod 33a forming an elongation of piston rod 33 there is mounted the second piston 41a shuttling back and forth in the cylinder 39. At the lowermost end of cylinder 39 there is mounted a pipe conduit 19 which may be connected with a manometer 44. The cylinder 39 and the piston 41a have a smaller diameter than the cylinder 38 and the piston 41, and the pipe 19 has a smaller diameter than the cylinder 39 and the piston 41a.

In the cylinder 38 there is furthermore provided an inlet valve 40 in the upper portion of the cylinder, and an outlet valve 45 in this lowermost portion and leading into a cylinder 39. The pistons 41 and 41a are provided with check valves 42 and 42a. so that the air can reach the other side of the pistons 41, 41a whenever the same move in upward direction.

In this embodiment of the invention exhaust gases are alternatingly passed into the spaces 16 and 23, respectively, thereby actuating the two sides of base plate 32 and membrane 31 alternatingly, thus moving the base plate 32 upwardly and downwardly, which reciprocating movement is transmitted to the pistons 41 and 41a in the cylinders 38 and 39 via the connecting rod 33, 33a.

The alternating introduction of the exhaust gases into the spaces 16 and 23, respectively, is effected via the cylinder 3, the sleeve 8 and the cylinder 6.

The pressure medium to be conveyed, for example air, is sucked into the upper portion of cylinder 38 via the valve 40 during the downward stroke of piston 41. During the upward stroke of the piston 41 the valve 40 is kept in closed position by force of the mounting pressure in the upper portion of cylinder 38. During the downward stroke the valve 42 in piston 41 opens and the pressure medium passes from the space above piston 41 into the space below the latter. At the next following downward stroke of piston 41 the pressure medium is forced into the upper portion of cylinder 39 via valve 45 and during the next following upward stroke of pistons 41, 42 the pressure medium is passed into the space below piston 41a via the valve 42a in the last mentioned piston. Thereafter the pressure medium is pushed into the pipe 19 via the valve 46 and from there into the object to be inflated.

Since the cylinder 39 has the same length as the cylinder 38 but is of much smaller diameter, and since furthermore the diameter of pipe 19 is still smaller than that of cylinder 39 the pressure is increased considerably. By suitably dimensioning the ratio of these three diameters, the desired pressure increase can be accomplished. By means of this embodiment of the present invention it is therefore possible to accomplish high pressures while still obtaining a handsome quantitative yield of conveyed pressure medium.

The movement of the base plate 32 can be facilitated into the direction in which the main work has to be done by means of a spring 43. The pump may furthermore be equipped with a manometer 44 and, if necessary, with safety valves.

In the embodiment shown in FIGURES 1 and 2 of the pump of the present invention the safety valves 4 and 5 can be dispensed with, if the openings 12 of sleeve 11 are longer than the distance between the openings 8 and in the cylinder 6. In that case a small outlet for the exhaust gases remains available in both the openings 8 and 10 in the central position of sleeve 11 in which otherwise the openings 8 and 10 will be closed. These openings fulfill the same function as a safety valve since the exhaust gases can evade therethrough.

Instead of a three-way cock a valve can be used in the conduit 34 establishing communication between the interior of conduit 16 and the outside as soon as a certain predetermined pressure is reached. It is also possible to dispense with a connection between conduits 34 and 35. In that case the connecting pipe of the device to be inflated has to be changed from the conduit 34 to the cond'uit communicating With cylinder 28 as soon as the pump has come to a standstill after having reached the maximum pressure of the first stage.

Experience has shown that the running motor is in no way disturbed by the inflating operation performed with the aid of its exhaust gases; a pressure up to /2 superatmospheric pressure does not influence the running motor, whereas a substantially smaller pressure is sufficient for the inflation. The required pressure is thus substantially below the normal pressure created in the muflier in the course of normal operation of an automobile motor.

It will be understood that this invention is susceptible to modification in order to adapt it to different usages and conditions, and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

What I claim is:

l. A pump for conveying and compressing a gaseous pressure medium by action of the exhaust gases of an internal combustion engine comprising, in combination, a casing, a displ-aceable dividing member in said casing dividing the interior thereof into at least one first space for the exhaust gases and at least one second space for the gas to be conveyed and compressed of varying inversely proportional volumes determined by the respective situation of said dividing member in said casing, inlet valve means and outlet valve means in the first space of said casing, and conduit means connecting the exhaust pipe of the internal combustion engine with said first space via said valve means, said casing having inlet and outlet check valve means therein opening into said second space, the exhaust gases alternatingly passing into said first space via said inlet valve means and exerting pressure on said displaceable dividing member and leaving said first space via said outlet valve means thereby causing said first and second space to expand and contract, respectively, and vice versa, alternatingly, and a control spring connecting said inlet and outlet valve means and said dividing member to control said inlet and outlet valve means so that the latter remain in their respective positions as long as possible and are moved into the opposite positions as soon as said displaceable dividing member has reached a predetermined position.

2. A pump for conveying and compressing a gaseous pressure medium by action of the exhaust gases of an internal combustion engine comprising, in combination, a casing, a flexible dividing member in said casing dividing the interior thereof into at least one first space for the emaust gases and at least one second space for the gas to be conveyed and compressed of varying inversely proportional volumes determined by the respective situation of said dividing member in said casing, said casing having a cylindrical portion opening into said first space with at least one inlet and at least one outlet opening therein, conduit means connecting the exhaust pipe of the internal combustion engine with said first space through said inlet opening, a slidable sleeve reciprocably mounted within said cylindrical portion and having one opening therein registrable with said inlet and outlet openings, said casing having inlet and outlet check valve means therein opening into said second space, means connecting said sleeve with said flexible dividing member for causing said sleeve to follow its reciprocating movements, said sleeve thereby alternatingly having its opening in registration with said inlet opening and said outlet opening in said casing, the exhaust gases alternatingly passing into said first space via said inlet opening and exerting pressure on said flexible dividing member and leaving said first space via said outlet opening thereby causing said first and second spaces to expand and contract, respectively, and vice versa, alternatingly.

3. A pump for conveying and compressing a gaseous pressure medium by action of the exhaust gases of an internal combustion engine comprising, in combination, a casing, a flexible dividing member in said casing dividing the interior thereof into at least one first space for the exhaust gases and at least one second space for the gas to be conveyed and compressed of varying inversely proportional volumes determined by the respective situation of said dividing member in said casing, said casing having a cylindrical portion opening into said first space with at least one inlet and at least one outlet opening therein, conduit means connecting the exhaust pipe of the internal combustion engine with said first space through said inlet opening, a slidable sleeve reciprocably mounted within said cylindrical portion and having one opening therein registrable with said inlet and outlet openings, said casing having inlet and outlet check valve means therein opening into said second space, means-connecting said sleeve with said flexible dividing member for causing said sleeve to follow its reciprocating movements, said sleeve thereby alternatingly having its opening in registration with said inlet opening and said outlet opening in said casing, the exhaust gases alternatingly passing into said first space via said inlet opening and exerting pressure on said flexible dividing member and leaving said first space via said outlet opening thereby causing said first and second spaces to expand and contract, respectively, and vice versa, alternatingly, and stop means for limiting the movement of said sleeve between its extreme end positions.

Lane July 15, 1913 Cox Jan. 17, 1950 

